Electric fence



Oct. 21, 1941. s. G. KLUMB 2,259,570

ELECTRIC FENCE Filed Jan. 30, 1939 @n/Ey l?. Umb

Patented Oct. 21, 1941.

2,259,570 momo mos Stanley G. Klumb, Milwaukee, Wis. Appiieation January 30. 1939, serial No. 253,677

schim.

This invention relates to improvements in electrically charged fences commonly termed electric lfences and of the type referred to in the copending application; Serial `No. 77,830, illed May 4, 1936, for Electric fence.

Heretofore, many schemes have been employed for eiectricallylcharging or energizing a fence wire; but in the majority of these schemes, the effectiveness of the shock to an animal coming in contact therewith was nullified to a large degree by leakage caused by partial grounding of the wire which precluded the application of a maximum charge on the wire.

It is, therefore, an object of this invention to provide an improved manner of charging an electric fence wire in vwhichy the impression of the desired eiIective charge on the fence is assured regardless of leakage in the fence circuit.

Another object of this invention is to provide a fence charger of the type shown in the aforementioned co-pending application in which a condenser is employed to build up an eective charge, having means incorporated therein for keeping the fence wire disconnected from the condenser forthe interval during which the condenser is being charged so as toY allow the condenser to be charged 'before being connected with the fence wire to thus insure maximum e'ectiveness.

With a view to safety, it is a further object of this invention to provide means for electrically charging or energizing a fence wire whereby an animal contacting the same does not receive a continuous high charge but receives shocks periodically for as long as the fence wire is contacted.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly deilned by the appended claims, it being understood that such changes in the precise embodiment of the herelndisclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates two complete examples of the physical embodiment of the invention constructed according to the best modesso far devised for the practical application of the principles thereof, and in which:

Figure l is a diagrammatic illustration of one application of this invention; and A Figure 2 is a diagram similar to Figure 1 showing a slightly modified embodiment of this invention.

Referring now particularly to the accompanying drawing, in which like numerals indicate like parts, the numeral i designates a fence wire of any suitable type carried by but insulated from posts 6 or other supports.

The fence' wire is electrically charged or energized by a charging unit, indicated generally VR. M. S.

by the numeral l; and in practice, the charging unit is preferably housed in a container and located wherever convenient. The vcharging unit l comprises a step-up transformer 8 having a primary l I adapted to be connected with a source of alternating current of commercial frequency or` any suitable A. C. supply desired, and a secondary comprising two windings Il and I2. The secondary winding Ii has one end connected to the plate I3 of a thermionic rectifier tube Il to which it provides high voltage and has its other end grounded.

'I'he lament I5 of the rectifier tube is supplied with low voltage from the secondary winding I2.. of the transformer. The unidirectional pulsating output of the tube Il is utilized to charge a condenser IB through an adjustable re'- sistance Il, the other side of the condenser being grounded. A charging circuit including the rectifier and the condenser is thus formed.

The output of the rectifier tube and the charging circuit is normally insulated from the fence wire by means of a gas tube I l and as a result (ai. substantial charge is built up in the conenser.

The charge which is built up in the 'conrectifier, acts as a reservoir and becomes charged Y to substantially the peak value of the pulsating current which is usually approximately 1.4 times the R. M. S. value of such current.

Thus for purposes of illustration, if the value of the output of the rectifier is 850 v.. the charge ot peak value which the condenser is capable of storing will be approximately 1.4 times 850 v. or 1190 v.

It will be seen,'therefore, that it is the function of the rectifier to providea unidirectional charging current for the condenser to permit building up a charge therein in excess of .the

voltage in the charging unit. Obviously, while a half wave rectier has been illustrated in the drawing. a full wave rectifier may be used with equal success to provide the required unidirecnot in anywise injure an animal coming in con tact with the wire.

As stated, the gas tube I8 normally insulates the fence wire from the charging circuit to allow a charge to be built up in the condenser; but upon the attainment of a. predetermined effective charge in -the condenser or a charge of ,sumciently high value to ionize the gas contents of the tube i3, the fence wire is electrically connected with the condenser. y A

Hence, upon grounding of the fence wire, the entire charge of the condenser is spontaneously discharged; and if the ground connection is through the body of an animal contacting the wire, the animal receives a sudden momentary shock of sucient intensity to be eective. Upon such discharge, the gas in the tube i8, no longer being subjected to the high charge of the condenser, deionizes to disconnect the fence from the condenser and consequently the charging circuit. Current from the rectiier tube i4 thus again iiows to the condenser and builds up a new charge therein; and as soon as the condenser is fully charged, the current ilow from the recti er tube ceases and the ionization of the gas in the tube l@ electrically reconnects the fence wire with the condenser.

Thus, it will be seen that the fencewire 5, if grounded, is periodically energized at substantially regular intervals. In the event it is desired to regulate the frequency of the condenser discharge through the fence wire, the resistance ii may be adjusted to regulate the charging rate of the condenser to any desired degree. If desired, a condenser iQ may be connected across the eelctrodes of the gas tube I to positively guard against the possibility of arcing between the electrodes of the tube in the event the gas does not completely deioniae after the fence has been grounded vand current again starts flowing in the charging circuit.

vMagnetic shunt blocks 2D may be inserted in the transformer core to limit the current in the secondary winding Il to a safe value and enable the charging unit to operate from any lighting source.

In the form of the invention shown in Figure 2, a relay 2l having a coil 22 connected in series with the rectiier tube output Vand the condenser is used to disconnect the fence wire from the condenser after the fence Wire is grounded and unloads its charge. f

In all respects, the charging circuit is substantially the same as that described in connection with Figure 1.

After grounding of the vfence wire, the flow of charging current from the rectifier tube to the condenser passes through' the coil 22 ofthe relay energizing the same. Upon energization of the relay, its armature 24 is moved out of engagement with the fence wire terminal 25 to break the connection between the fence wire and the condenserand its charging circuit to again permit the condenser to become charged.

Afterthe condenser is charged, the ow of current from the rectifier tube ceases and consequently deenergization of the relay allows alight spring 26 to pull the armature 24 into contact with the terminal 25 to reconnect the fence wire with the condenser.

If desired, a condenser 21 may be connected in parallel with the relay coil 22 to iilter out the D. C. ripple, thus insuring smooth functioning of the relay.

It is also preferable to connect a condenser between the fence and the ground as shown at 28 in each of the embodiments shown, to eliminate or suppress radio interference.

From the foregoing description taken inconnectlon with the accompanying drawing, it will be readily apparent to-those skilled in the art, that this invention assures maximum eiectiveness by, keeping the fence wire disconnected from the condenser for the interval during which the Icondenser is being charged. This enables the condenser to be fully charged regardless of any electrical leakage in the fence circuit.

What I claim as my invention is:

l. In an electric fence: a fence wire insulated from the ground; a step-up transformer having a primary connectible with a source of alternating current; a rectier connected with the high voltage secondary of the transformer; a gas tube connected between the fence wire and the rectifier and having a minimum operating charac-v teristic'such as to prevent the flow of current onto the fence wire from the rectifier, the discharge Aoi said gas tube requiring grounding of the fence wire and ionization of its gas' contents brought about by the impression thereon of a potentialof predetermined value in excess of the R. M. S. value of the rectiiier output; and a condenser connected with said gas tube and the rectifier for building up the rectier potential at least to said predetermined value at which the gas in the tube is caused to ionize, whereby the condenser may spontaneously .discharge through the gas tube to eiect the application of a sudden eelctrical impulse onto the fence wire during grounding of the same.

2. In an electric fence: a fence wire insulated from the ground; a condenser; a ycharging circuit for the condenser including a source of unidirectional pulsating current eiective to charge the condenser to a predetermined value, and in which the current ceases flowing when the condenser becomes charged to said value; and means for electrically connecting the fence wire with the condenser, said means being responsive to the iiow of current in the charging circuit to disconnect the fence wire from the condenser.

' 3. In an electric fence: a fence wire insulated from the ground; a source of unidirectional pulsating current including a rectifier; a condenser adapted to be charged from the output of the rectifier to a value above the R. M. S. value of the rectier output; a relay having its coil connected in series with the condenser and the rectifier to be energized by the output thereof as long as charging current continues to ow to the condenser and to be deenergized upon the cessation of current ow when the condenser becomes charged; and means controlled by said relay to electrically connect the fence wire with the condenser upon deenergization of the relay coil.

4. An electric fence comprising: a condenser; a shocking circuit constituting the sole means for discharging the condenser and consisting of the condenser, one side of which is grounded, a fence wire insulated from the ground, and means in- 'cluding a control device having a minimum operating characteristic connecting the fence wire with the otherside of the condenser so that a charge on the condenser in excess of the minimum required to operate said control device renders the same operative and discharges the condenser whenever the circuit is completed between the fence wire and ground; and a charging circuit for charging the condenser including a source of unidirectional pulsating current of an R. M. S. value below the critical value of said control device, and means connecting said source with the ungrounded side of the condenser so as to build up a charge therein while the control device is inoperative.

5. In an electric fence: a source of unidirectional pulsating current; a condenser connected with said source to store up an electrical charge therein of a value approximating the peak voltage of said source; a circuit fed by the condenser and constituting the sole means for discharging the same; means for holding said circuit open 'until the charge on the condenser attains said value approximating peak voltage of the source; and a fence wire insulated from the ground and so connected with said circuit that grounding of the fence wire is a prerequisite to closure of said circuit and current flow in said circuit effects energization of the fence wire.

6. In an electric fence: a bare fence wire insulated from the ground; a condenser in which a predetermined high voltage charge is adapted to be built up; a source of unidirectional pulsating current the R. M. S. voltage of which is less than said predetermined high voltage; means for connecting said source with the condenser so that the condenser becomes charged with said predetermined high voltage; a fence energizing circuit constituting the sole means for discharging the condenser and so connected with the fence wire that grounding of the fence wire is'a prerequisite to discharge of the condenser; and a critical value control device connected in said circuit for holding said circuit open ,until the charge on the condenser reaches said predetermined high voltage in excess of the R. M. S. voltage of the source despite a possible grounded condition of the fence wire.

7. In an electric fence: a bare wire insulated from the ground and adapted to be grounded byan animal contactingthe same; a condenser in which a predetermined high voltage charge is adapted to be built up; a source of unidirectional pulsating current the R. M. S. voltage of which is less than said predetermined high voltage; means for connecting said source with the condenser so that the condenser becomes charged with said predetermined high voltage; and a normally open shocking circuit constituting the soie means for discharging the condenser and comprising the bare wire grounded by an animal or other grounding connection and a critical value control device connected in series, said critical value control device holding the shocking circuit open until the charge on the condenser reaches said predetermined high voltage in excess of the R. M. S. voltage of the source despite a grounded condition of the bare wire.

8, An electric fence comprising: a bare wire insulated from the ground and adapted to be grounded by an animal contacting the same; means for charging the fence wire with high voltage electricity so that an animal contacting the wire receives a shock, said means comprising, a condenser in which the high voltage is adapted to be built up, a condenser charging circuit including the condenser, a source of unidirectional pulsating current, the R. M. S. value of which is less than the voltage of the charge to be built up in the condenser, and electrical connections between said source and the condenser; and a normally open shocking circuit constituting the sole means for discharging the condenser and including the condenser, the fence wire, ground and a gaseous discharge tube all connected in series, said gaseous discharge tube holding the shocking circuit open despite possible grounding of the fence wire until the charge on the condenser reaches a predetermined value in excess of the R. M. S. value of the current source. I

9. An electric fence comprising: a bare wire insulated from the ground and adapted to be grounded by an animal contacting the same; means for charging the fence Wire with high voltage electricity so that an animal contacting the Wire receives a shock, said means comprising, a condenser in which the high voltage is adapted vto be built up, a condenser charging circuit including the condenser, a source of unidirectional pulsating current, the R. M. S. value of which is less than the voltage of the `charge to be built up in the condenser, and electrical connections between said source and the condenser; and a normally open shocking circuit constituting the sole means for discharging the condenser and including the condenser, the fence wire, ground and a critical value control device all connected in series, said critical value control device holding 

